---
title: "replace(commandBuffer:)"
framework: realitykit
role: symbol
role_heading: Instance Method
path: "realitykit/lowlevelbufferresource/replace(commandbuffer:)"
---

# replace(commandBuffer:)

Retrieves a Metal buffer for GPU replacement. The buffer’s contents are in an uninitialized state. The renderer waits for the command buffer to complete before using the buffer for rendering.

## Declaration

```swift
final func replace(commandBuffer: (any MTLCommandBuffer)?) -> any MTLBuffer
```

## Parameters

- `commandBuffer`: The command buffer writing to this buffer, or nil to skip synchronization.

## Return Value

Return Value A MTLBuffer ready for GPU write operations.

## See Also

### Replacing buffer contents

- [replace(_:)](realitykit/lowlevelbufferresource/replace(_:).md)